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Topics covered in this episode:

• Cyclopts: A CLI library
• * The future of Python web services looks GIL-free*
• * Free-threaded GC*
• * Polite lazy imports for Python package maintainers*
• Extras
• Joke

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Michael #1: Cyclopts: A CLI library

• A CLI library that fixes 13 annoying issues in Typer
• Much of Cyclopts was inspired by the excellent Typer library.
• Despite its popularity, Typer has some traits that I (and others) find less than ideal. Part of this stems from Typer's age, with its first release in late 2019, soon after Python 3.8's release. Because of this, most of its API was initially designed around assigning proxy default values to function parameters. This made the decorated command functions difficult to use outside of Typer. With the introduction of <code>Annotated</code> in python3.9, type-hints were able to be directly annotated, allowing for the removal of these proxy defaults.
• The 13:
  • Argument vs Option
  • Positional or Keyword Arguments
  • Choices
  • Default Command
  • Docstring Parsing
  • Decorator Parentheses
  • Optional Lists
  • Keyword Multiple Values
  • Flag Negation
  • Help Defaults
  • Validation
  • Union/Optional Support
  • Adding a Version Flag
  • Documentation

Brian #2: The future of Python web services looks GIL-free

• Giovanni Barillari

• “Python 3.14 was released at the beginning of the month. This release was particularly interesting to me because of the improvements on the "free-threaded" variant of the interpreter.

  Specifically, the two major changes when compared to the free-threaded variant of Python 3.13 are:

  • Free-threaded support now reached phase II, meaning it's no longer considered experimental
  • The implementation is now completed, meaning that the workarounds introduced in Python 3.13 to make code sound without the GIL are now gone, and the free-threaded implementation now uses the adaptive interpreter as the GIL enabled variant. These facts, plus additional optimizations make the performance penalty now way better, moving from a 35% penalty to a 5-10% difference.”
• Lots of benchmark data, both ASGI and WSGI
• Lots of great thoughts in the “Final Thoughts” section, including
  • “On asynchronous protocols like ASGI, despite the fact the concurrency model doesn't change that much – we shift from one event loop per process, to one event loop per thread – just the fact we no longer need to scale memory allocations just to use more CPU is a massive improvement. ”
  • “… for everybody out there coding a web application in Python: simplifying the concurrency paradigms and the deployment process of such applications is a good thing.”
  • “… to me the future of Python web services looks GIL-free.”

Michael #3: Free-threaded GC

• The free-threaded build of Python uses a different garbage collector implementation than the default GIL-enabled build.
• The Default GC: In the standard CPython build, every object that supports garbage collection (like lists or dictionaries) is part of a per-interpreter, doubly-linked list. The list pointers are contained in a PyGC_Head structure.
• The Free-Threaded GC: Takes a different approach. It scraps the PyGC_Head structure and the linked list entirely. Instead, it allocates these objects from a special memory heap managed by the "mimalloc" library. This allows the GC to find and iterate over all collectible objects using mimalloc's data structures, without needing to link them together manually.
• The free-threaded GC does NOT support "generations”
• By marking all objects reachable from these known roots, we can identify a large set of objects that are definitely alive and exclude them from the more expensive cycle-finding part of the GC process.
• Overall speedup of the free-threaded GC collection is between 2 and 12 times faster than the 3.13 version.

Brian #4: Polite lazy imports for Python package maintainers

• Will McGugan commented on a LI post by Bob Belderbos regarding lazy importing

• “I'm excited about this PEP.

  I wrote a lazy loading mechanism for Textual's widgets. Without it, the entire widget library would be imported even if you needed just one widget. Having this as a core language feature would make me very happy.”

  https://github.com/Textualize/textual/blob/main/src/textual/widgets/__init__.py

• Well, I was excited about Will’s example for how to, essentially, allow users of your package to import only the part they need, when they need it.

• So I wrote up my thoughts and an explainer for how this works.
• Special thanks to Trey Hunner’s Every dunder method in Python, which I referenced to understand the difference between __getattr__() and __getattribute__().

Extras

Brian:

• Started writing a book on Test Driven Development.
  • Should have an announcement in a week or so.
  • I want to give folks access while I’m writing it, so I’ll be opening it up for early access as soon as I have 2-3 chapters ready to review. Sign up for the pythontest newsletter if you’d like to be informed right away when it’s ready. Or stay tuned here.

Michael:

• New course!!! Agentic AI Programming for Python
• I’ll be on Vanishing Gradients as a guest talking book + ai for data scientists
• OpenAI launches ChatGPT Atlas
• https://github.com/jamesabel/ismain by James Abel
• Pets in PyCharm

Joke: You're absolutely right

Portland and Denver play a fascinating game in a contrast of styles, with Jerami Grant getting revenge against his old team. 

Ja Morant pouts his way through a winnable game against the Lakers, then voices displeasure in the media afterward.

Kawhi Leonard sends the Pelicans home with another loss.

The Knicks’ defense proved the perfect matchup for how the Bulls want to play offense.

Plus a bit more on every other game of the night.

Blazers vs. Nuggets — 0:00

Lakers vs. Grizzlies — 25:32

Clippers vs. Pelicans — 40:11

Hawks vs. Pacers — 49:52

Suns vs. Jazz — 51:46

Bulls vs. Knicks — 53:16

Celtics vs. Sixers — 1:01:39

Raptors vs. Cavaliers — 1:10:24

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OA1203 - Happy Halloween! We take shelter from a year of ghoulish legal news in the COURTHOUSE OF HORROR, a cabinet of macabre legal curiosities including:

1. “SO I TRADEMARKED AN AXE MURDERER”: The historic Lizzie Borden House takes a whack at a nearby coffee shop

2. “THE BONE DETECTOR”: Recent patent bar survivor Jenessa Seymour brings us the unbelievable story of the spookiest--and silliest!--lie detector ever registered by the US Patent & Trademark Office

3. “ATTACK OF THE TORTIOUS CLOWNS”: Can you sue a haunted house for your fright-related injuries? 

4. “THE GREENBRIER GHOST”: The bizarre tale of how a victim’s testimony from beyond the grave helped to convict her killer in an 1896 West Virginia murder trial

5. “CANDYMAN 5: SUMMARY JUDGMENT”: In a tasty conclusion to last year’s Halloween footnote on consumers disappointed with the spookiness of their seasonal treats, a Florida federal judge finds as a matter of law that there is no wrong way to make a Reese’s.

Finally, we close on a serious note with Jenessa’s guide to how every registered voter can do their part next week to change the plot of our ongoing American horror story.

1. Order in Ghost Adventures LLC v. Miss Lizzie’s Coffee, LLC, No. 23-2000 (1st 

Cir.)(Selya, J.)(11/15/2024)

2. “Federal Judge Known for Polysyllabic Prose Dies at 90,” Trip Gabriel, The New York Times, (3/21/2025)

3. “Would You Confess Your Criminal Misdeeds to This Skeleton?,” Cara Giaimo, Atlas Obscura (5/16/2017)

4. “Apparatus for Obtaining Criminal Confessions and Photographically Recording Them,” Patent #1749090, H.A. Shelby (filed 8/10/1927)

5. “The Greenbrier Ghost Reexamined,” Greenbrier Historical Society, Arabeth Balseko (1/20/2022)

6. Summary judgment order in Munoz v. Six Flags St. Louis LLC (10/12/2022)(Wallach, J.)

7. Order granting motion to dismiss in Vidal et al v. The Hershey Company, FLSD No. 24-60831 (9/19/2025)(Damian, J.)

8. “Your Cheat Sheet To The 2025 General Elections,” Daniel Nichanian, Bolts (10/1/2025)

Check out the OA Linktree for all the places to go and things to do!

Zach and Denver Nuggets head coach Michael Malone go behind the scenes on the Nuggets journey to the 2023 NBA title, then ESPN's Ohm Youngmisuk join to talk the Clippers at the crossroads, the James Harden situation, and more.  Learn more about your ad choices. Visit megaphone.fm/adchoices

Bill rambles about 90's heroine sheik, roller coaster malfunctions, and heli-hogging.

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The Ringer’s Bill Simmons, Chris Ryan, and Van Lathan don’t know what death is after rewatching the 1981 return of Michael Myers in ‘Halloween II,’ starring Jamie Lee Curtis and Donald Pleasence. Producers: Craig Horlbeck, Ronak Nair, Chia Hao Tat, and Eduardo Ocampo A Mountain of Movies® on Paramount+. Stream now! A House of Dynamite, on Netflix October 24th. A State Farm agent can help you choose the coverage you need. Like a good neighbor, State Farm is there.® Learn more about your ad choices. Visit podcastchoices.com/adchoices

The Ringer’s Bill Simmons and Joe House talk about their “uh-oh” teams before doing a power poll 10 days into the NBA season (4:01). Then, Peter Schrager joins the pod to help Bill and House make their Ringer 107 picks (41:04). Host: Bill Simmons Guests: Joe House and Peter Schrager Producers: Chia Hao Tat and Eduardo Ocampo 15% off $15+ on NFL Gamedays with CODE: GAMEDAY at https://littlecaesars.onelink.me/vc9i/n15m71zn The Ringer is committed to responsible gaming. Please visit⁠⁠ www.rg-help.com⁠⁠ to learn more about the resources and helplines available. Learn more about your ad choices. Visit podcastchoices.com/adchoices

Python has many string formatting styles which have been added to the language over the years. Early Python used the % operator to injected formatted values into strings. And we have string.format() which offers several powerful styles. Both were verbose and indirect, so f-strings were added in Python 3.6. But these f-strings lacked security features (think little bobby tables) and they manifested as fully-formed strings to runtime code. Today we talk about the next evolution of Python string formatting for advanced use-cases (SQL, HTML, DSLs, etc): t-strings. We have Paul Everitt, David Peck, and Jim Baker on the show to introduce this upcoming new language feature.

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